U.S. Pat. No. 3,418,991, issued Dec. 31, 1968 and assigned to the assignee of this invention, describes an electric fuel pump in a motor vehicle fuel tank having a regenerative turbine pump including an open-vane impeller rotatable at high speed in a housing of the pump. As used herein, open-vane regenerative turbine pump vanes are vanes projecting radially from an impeller hub defining wedge-shaped vane pockets between adjacent pairs of vanes which pockets are substantially completely open on both sides of the respective pockets. In the aforesaid U.S. Pat. No. 3,418,991, the vanes on the open-vane impeller are irregularly spaced around the circumference of the hub for noise suppression.
U.S. Pat. Nos. 4,209,284 and 4,734,008, issued Jun. 24, 1980 and Mar. 29, 1988, respectively, and assigned to the assignee of this invention, describe electric fuel pumps in motor vehicle fuel tanks each having a two-stage regenerative turbine pump including a pair of open-vane impellers with irregularly spaced vanes. In the aforesaid U.S. Pat. No. 4,734,008, one of the open-vane impellers also has a hub including a plurality of radial spokes which define fan blades for improving the vapor handling characteristics of the pump.
An open-vane regenerative turbine pump impeller according to this invention is a novel alternative o the impellers described in the aforesaid U.S. patents.